With the popularization of color photographic light-sensitive materials, the color development process has been more and more simplified and shortened. On the other hand, the requirement for images having a high quality has increased more and more.
In such circumstances, photographic light-sensitive materials for color prints, have been investigated to improve their color reproducibility and tone reproducibility, to shorten the processing time, and to improve the sharpness.
It has been recently found that a high silver chloride emulsion is preferred as a silver halide emulsion for quick processing and such a technique has been widely employed.
In regard to image quality, particularly from the viewpoint of improving on image sharpness, a method of using dyes for preventing irradiation has been proposed.
For example, dye improvements are described in JP-A-50-145125, JP-A-52-20830, JP-A-50-147712, JP-A-59-111641, JP-A-61-148448, JP-A-61-151538, JP-A-61-151649, JP-A-61-151650, JP-A-61-151651, JP-A-61-170742, JP-A-61-175638, JP-A-61-235837, JP-A-61-248044, JP-A-62-164043, JP-A-62-253145, JP-A-62-253146, JP-A-62-253142, JP-A-62-275262, and JP-A-62-283336 (the term "JP-A" as used herein means an "unexamined published Japanese patent application"), Research Disclosure (RD), No. 17643, page 22 (Dec., 1978), and ibid, No. 18716,page 647 (Nov., 1979).
Also, a method of forming an antihalation layer (AH) in a color photographic light-sensitive material for the same purpose is described, for example, in U.S. Pat. Nos. 2,326,057, 2,882,156, 2,839,401, and 3,706,563, JP-A-55-33172, JP-A-59-193447 and JP-A-62-32448.
JP-A-63-286849 also describes that the optical reflection density on use of the above-described diffusible dyes or coloring agents for AH is increased over a certain density.
However, when the optical reflection density is increased, the sensitivity is greatly decreased with the improvement of the sharpness. Hence it is difficult to improve sharpness while maintaining a sufficient practical sensitivity using only the above-described means.
Also, to increase the reflection density it is necessary to use a large amount of dye(s) but the use of a large amount of dye results in a softening the gradation, which is one of the reasons why a practical high reflection density is not obtained.
The method of forming AH requires an addition of one new layer to the conventional layer structure, which undesirably increases the difficulty in the production of the photographic light-sensitive material.
To solving these problems, improvement in supports has been investigated.
A baryta-coated paper has hitherto been used as a support for light-sensitive materials for color prints but recently for shortening the photographic processing time, a waterproof or resin-coated paper formed by coating polyethylene on both surfaces of a base paper has been used. In this case, to maintain the sharpness of the print image on the waterproof paper at the level of sharpness on a baryta-coated paper, titanium oxide or zinc oxide is dispersed in the polyethylene layer but the sharpness is still inferior to that achieved presently in using a baryta-coated paper. Improvement in the polyethylene layer containing titanium oxide for the above-described purpose is described, e.g., in JP-B-58-43734 (the term "JP-B" as used herein means an "examined Japanese patent application"), JP-A-58-17433, JP-A-58-14830, and JP-A-61-259246.
Also, a method of coating a coating composition containing an unsaturated organic compound having one or more double bonds in the same molecule and polymerizable by electron rays and a white pigment on a base paper and hardening the layer by applying electron rays while heating to form a waterproof resin layer or layers on the base paper is described in JP-A-57-27257, JP-A-57-49946, JP-A-61-262738, and JP-A-62-61049.
A silver halide photographic material using a mirror plane reflective or secondary diffusion reflective support is described, e.g., in JP-A-63-24251 and JP-A-63-24253.
However, by improvement only of a support, the increase in improvement in sharpness is still insufficient and development of additional improvements is required.